As the world population continues to age, cardiovascular procedures will grow in frequency and complexity. In order to improve the safety and efficacy of such procedures, the complication of embolism associated with those procedures must be addressed.
An embolism is when thrombus or atheroma or calcium breaks loose from a patient's vasculature during a procedure and migrates distally and lodges in a peripheral vessel causing ischemic injury to the end organ.
A particularly acute complication is a cerebral embolism where an emboli lodges in one of the arteries of the brain and thus causes an injury to the brain. Accordingly, in a preferred embodiment, the invention focuses primarily on cerebral protection during heart operations such as coronary artery bypass surgery (CABG) and valve replacement, the latter being performed either by open chest surgery or through percutaneous delivery, e.g., trans-catheter aortic valve replacement (TAVR).
Traditional cerebral protection during open or closed heart procedures has involved administration of blood thinners (e.g. anticoagulants). However, this approach is directed more to the risk that arises due to the bleeding caused by surgical incisions. Such blood thinners do not address complications where the embolism is not responsive to anticoagulation.
Other methods include the use of aortic cannulas which have filters incorporated (e.g., Embolex) in the aorta as a way of protecting the brain. However, the large size and rigidity of these cannulas make them somewhat cumbersome.
More recently, in connection with TAVR procedures, surgeons have used diverters or filtration devices such as CLARET and EMBRELLA. Information regarding these devices are described and explained in the following references:                1. “Embolic Protection during TAVI Embrella,” Nikos Werner, Universitätsklinikum Bonn, Bonn, Germany, CS Frankfurt 2012.        2. “Brain Damage—Will Embolic Protection Devices Reduce Strokes After TAVR?”, Andreas Baumback, MD, FRCP, FESC, Bristol Heart Institute, University Hospitals Bristol, ICI 2012.        3. “CardioLogical Receives Patent for Aortic Embolic Protection Devices to Prevent During TAVR,” Diagnostic and Interventional Cardiology, Apr. 12, 2013, www.dicardiology.com/article/cardiological-receives-patent-aortic-embolic-protection-devices-prevent-during-tavr, accessed Apr. 28, 2013.        4. “Emboline,” www.emboline.com/technology.html, accessed Apr. 28, 2013.        5. “Intraprocedural Intraaortic Embolic Protection With the EmboIX Device in Patients Undergoing Transaortic Transcatheter Aortic Valve Implantation (TAo-EmboIX),” ClinicalTrials.gov, clinicaltrials.gov/ct2/show/NCT01735513, accessed Apr. 28, 2013.        6. “Embolic Protection Devices for TAVR Show Promise,” TCTMD, The source for Interventional Cardiovascular News and Education, www.tctmd.com/show.aspx?id=110221&AspxAutoDetectCookieSupport=1, accessed Apr. 28, 2013.        
These devices can essentially be divided into two categories: 1. Flow diverters where the emboli are diverted from entering vessels, e.g., the cerebral vessels; and, 2. Filtration devices where the emboli are captured and removed from the blood stream entirely.
The reliability and effectiveness of these devices is yet to be reliably verified. The need for some type of embolism protection, however, remains essential. Accordingly, there is an ongoing need for the development of systems and methods of protecting patients from emboli that are safe and effective. Accordingly, it is an object of the present invention to provide a system and method of more effectively providing protection from embolism to a patient during surgical procedures, and particularly protection from cerebral embolism.